This program aims to identify inhibitors of the 4'-phosphopantetheinyltransferase (PPTase) PptT associated with mycolic acid production in Mycobacterium tuberculosis (Mtb). PptT is responsible for activation of mycolic acid synthase, an essential protein involved in the biosynthesis of the mycobacterial cell wall and a newly validated drug target. We have recently completed a high-throughput screening (HTS) effort to identify inhibitors against Sfp, the Bacillus subtilis surfactin PPTase, in collaboration with the NIH Chemical Genomics Center (NCGC). Here we seek to probe the hits identified in this screen for activity against PptT and evaluate their antibacterial activity against wild type and drug resistant Mtb strains. Given our preliminary results from the Sfp HTS effort, the development of a robust and general PPTase assay, the importance of this pathogen for drug development, and the recent validation of PptT as a druggable target with potential for antibiotic development, we anticipate discovery of a new class of antitubucular compounds within the timeframe of this project. PUBLIC HEALTH RELEVANCE: Mycobacterium tuberculosis (Mtb) is the leading cause of death in the world from a bacterial infectious disease, affecting 1.8 billion people/year. This program examines the development of a new class of therapeutics that target the 4'-phosphopantetheinyltransferase (PPTase) PptT associated with mycolic acid production in Mycobacterium tuberculosis (Mtb) with the goal of identifying a panel of lead compounds within the funded period,